Manufacture and production of threads, filaments, and the like from viscose



Patented May 19, 1925.

STATES CHARLES FREDERICK CROSS, F LINCOLNS COURTAULDS LIMITED,

INN, LONDON, NGLAND, Assron'oia 'ro OF LONDON, ENGLAND.

MANUFACTURE AND PRODUCTION OF THREADS, FILAMENTS, AND THE BIKE FROM VISCOSJE.

N0 Drawing. 1 Application filed May 5,

To aiZZ whom, it may concern."

Be it known that l, CrrARLns FREDERICK- Cnoss, a subject of theliin of Great Britain, residing at 3 and 4 l l ew Court, Lin- F colnslnn, in the county of London. England. have'invented new and useful Improvements in the Manufacture and Production of Threads, Filaments, and the like from Viscose, of which the following is a specification. i

7 In the specification of British Letters Patent 8,0 l of 1906 it is stated that, in the production of artificial silk from viscosc, the viscose, after having been coagulated in a suitable bath into the form of a thread, can be passed through a second bath containing an alkali silicate in solution, for the purpose of preventing the single filaments fromcsticking together. This method of producing artificial silk has, however, not come into general use the viscose being at present generally precipitated directly in an acid bath.

The present invention is based on the discovery that an aqueous solution of an alkali silicate (especially alkali silicates of the acid type) precipitation, or coagulation, of viscose in the production of threads, filaments and the like, of artificial silk. For instance, on passing viscose (which may be repared and matured in the usual way) t rough fine holes in a jet into a bath containing the alkali silicate (for example sodium silicate of high ratio of SiQ to Na O) fine threads, filaments and the like can be obtained, which, after having been fixed in the ordinary, or any suitable, manner, can be subjected to the usual, or any suitable, manipulation, or finishing treatment, the resulting artificial silk being of excellent quality.

The following is an example of how this invention may be carried into effect, but it is not limited to this example.

Example.

Viscose, such as is ordinarily prepared for the production of artificial silk by the .into a solution containing twenty per cent can be employed for the direct 1 threads,

1924. Serial No. 711,241.

acid method of precipitation, is projected by weight of a silicate of soda of the composition 2Na,U-(Si0,, and maintained at a temperature of from d0 to 50 centi grade. This bath, although strongly alkaline in the ordinary sense, has the property of coagulating the viscose to the solid form, and this, after fixation (for instance by one per cent sulphuric acid) and after any other requisite, or desirable, manipulation, or treatment, results in. lustrous threads, filaments and the like, of excellent quality.

li ith the understanding thatthe foregoing example is but illustrative of my in vention, and that the desired results can be obtained without exact conformity thereto, I claim as my invention:

1. A process for the production of threads, filaments and the like, from viscose, the said, process comprising the step of extruding the viscose into a bath contain ing an alkali silicate in aqueous solution and thereby coagulating the viscose.

2. A process for the production of threads, filaments and the like, from viscose, the said process comprising the step of extruding the viscose into a bath containing in aqueous solution, an alkaline silicate of high ratio of silica to: alkali oxide, and thereby coagulating the viscose.

3. A process for the" production of filaments and the like, from viscose, the said process comprising the step of extruding the viscose into an aqueous solution containing twenty per cent by weight of sodium silicate of the-composition 2Na,O- 7SiO and'maintained at a temperature of from 40 to 5 centigrade and thereby coagulating the viscose.

In testimony whereof I have signed my name to this specification in the presence of 90 two subscribing witnesses.

CHARLES FREDERICK CROSS.

Witnesses:

GILLARD FLETCHER TYsoN, EDNA TAYLOR. 

